Gas cylinders containing a compressed fuel gas are commercially available in a variety of sizes that can be used as a source of heat (i.e., heating source). Gas cylinders that are of a portable size are often not reusable (i.e., refillable). After the compressed fuel gas has been used as a heating source, the gas cylinders can present an environmental hazard if they are not disposed of properly. More specifically, the gas cylinders often contain some residual fuel (i.e., residual compressed gas) inside after normal use. If the gas cylinders undergo corrosion, the residual fuel can be released. This release can pose both an environmental problem and a potential fire or explosion hazard.
Fuel gases are often used to heat metal in various metallurgical applications. One commonly used fuel gas for fusion welding and brazing is acetylene. Acetylene has a number of drawbacks as a fuel gas, particularly for use in portable gas cylinders. It is explosive if the pressure exceeds about 15 pounds per square inch (psi). For this reason, acetylene is usually dissolved in acetone or another organic solvent to improve its stability. Further, various porous filler materials are typically placed in gas cylinders used with acetylene to further improve stability. The addition of these porous materials can adversely impact the total weight of the gas cylinder containing acetylene. Further, addition of these porous materials can create a disposal problem because the used porous materials may be considered a hazardous waste.